Shapeways is a service company. They have a (large) number of 3d printers in their facility.
You would design and upload a 3d model to their website, then pay for them to print that model on one of their printers and send it to you.
They also have a number of designers with shops (such as mine) that you can purchase printed items from other people's shop.

Shapeways does NOT offer Design Software.
Sending a 3d file to Shapeways does not involve writing any kind of "program for their printer". The printers understand several common 3d formats such as STL, WRL, DAE, and the printers just take the uploaded geometry and print it.

Just before your model is printed, Shapeways will verify that the geometry is printable, but they don't offer the option to "fix" your geometry.

Patience, Persistance, Politeness - the 3Ps will help us get us to Perfect Printed Products